The first
radios were substitutes for a pair of copper wires and were com-monly referred
to as wireless communications. These radios were used tobridge gaps
that couldn't be managed with wire lines, such as between ships at sea
and the shore. Later, as FSK, facsimile, video, and encryption became popular,
special purpose boxes were invented to encode and decode base band signals
that were transmitted over these simple radio channels.

As the mobility
of communications equipment became more and more important, the hardware
in these external boxes were miniaturized and incorporated into the radios.
The advent of powerful Digital Signal Processing (DSP) chips and controlling
microprocessors enabled the very complex coding and modulation schemes
described earlier in this handbook. These schemes have been used to increase
the efficient use of bandwidth up to the point that is now approaching
theoretical limits.

What challenges
await military tactical radio communications equipmentin the 21st
Century? The answer to this can be found by looking at thechanges that
have emerged on the modern battlefield. During the Gulf War, we witnessed
a dramatic increase in the operational tempo of the battlefield. Command
and control communications were lost as the military forces moved rapidly
across the flat desert terrain, outpacing theconventional
military communication systems. Increased information flow demands the
use of data communications in place of voice communications, with an ever-
increasing thirst for bandwidth. Critical battlefieldinformation
must flow both horizontally and vertically, driving the needfor tactical
networking.

There also
emerges an increased need for situational awareness (SA) knowing the
precise location of military assets and personnel. As force sizes are reduced
through cuts in military spending, accurate situationalawareness
is a key to maintaining the dominant level of force lethality. Inthe future,
SA will become a background task of the command and controlcommunications
structure. Position information will be securely appendedto all voice
and data traffic, and routed to a SA collection point so thatmilitary
commanders can plan and execute a successful military campaign.Finally,
increased sophistication of enemy forces will demand the use ofimproved
information security (INFOSEC) techniques. This includes stronger,embedded
encryption/ decryption devices used for all voice and data traffic, advanced
electronic counter- counter measures (ECCM) methods to sustain communications
in the presence of intentional jamming, and the use of Low- Probability
of Intercept (LPI) and Low Probability of Detection (LPD) methods to protect
forward- deployed troops operating in hostile areas.

Tactical Networking
 Simple, Seamless and Secure Communications

During this
past decade, we have all witnessed the impact the growth of the commercial
Internet has had on countries around the globe. It demonstrates the power
of seamless connectivity and the benefits gained from establishing common
interfaces and protocols. Today the commercial Internet is starting to
embrace the challenges presented by a wireless world. Many of these challenges
are the same as those encountered in a modern military communications system
 the demand for seamless connectivity, self- forming and healing networks,
and secure communication links  to name but a few. Successful military
communications equipment of the future will embrace this technology, building
on the technological base established from enormous investments in the
commercial sector.

Tactical networking
will become an enabler for many military applicationsin the 21st
Century. Example applications include: command/ control systems; situational
awareness systems; automatic range extension; tacticalmessaging
systems; fire- control systems; full duplex and simultaneousvoice/ data
systems; common database access; even combat net radiointerface
(CNRI) systems which link tactical and land- based infrastructures.

Radios, such
as the Harris Falcon  II Tactical Radio Family, will providea seamless
IP networking interface to other systems and applicationprograms.
New systems will be quickly and cost- effectively developed usingcommercial-
off- the- shelf (COTS) tools and applications. Advanced channel access
protocols are under development to ensure the maximum effectiveuse of the
available frequency spectrum. Packet data transmissions willenable multiple
applications to be simultaneously supported on a priority-driven basis
and will allow voice and data traffic to coexist, even on asingle, narrowband
radio channel.

Packet data
transmission, combined with very fast receive- to- transmitswitching
techniques, allow a simplex channel (one that alternately trans-mits and
receives on the same frequency) to emulate the performance offull- duplex
channels (one that receives and transmits on different frequencies simultaneously).
It used to take two radios for retransmission, one to receive and the other
to transmit simultaneously on another frequency.

Cutting edge
radios of today can accomplish this with only one radio.

The trend
in this area is to build a seamless network supporting any combi-nation of
point- to- point and point- to- multipoint voice and/ or data connections.
Information will be encrypted and decrypted only at the origination and
destination stations, ensuring information securing from end- to- end.

Higher Speed
Data

During conflict,
timely information collection and dissemination is critical to operating
within the enemys decision cycle. This need for increased information
flow is driving the desire for ever- increasing data transmission rates.
The latest generation of tactical radios offers a 4x increase over those
currently fielded. This increase in data rate significantly increases message
throughput and reduces the message latency.According
to Chester Massari, Harris RF Communications division president, "Data
transmission is the future of military communications. As one of the pioneers
in this area, we can send high- speed imagery and data across the radio
spectrum better than anyone in the industry  plus, we offer this capability
for land, sea, and air missions."

Where Do We
Go From Here?

It is natural
to ask the question, where do we go from here? Of course,with technology
expanding at an ever- increasing rate, it is difficult topredict specifics
more than a year or so in the future, but these are someof the important
trends that are likely to influence radio technologyfor many
years to come.